| Texto completo | |
| Autor(es): |
Barghathi, Hatem
[1]
;
Hrahsheh, Fawaz
[1, 2, 3]
;
Hoyos, Jose A.
[4]
;
Narayanan, Rajesh
[5]
;
Vojta, Thomas
[1]
Número total de Autores: 5
|
| Afiliação do(s) autor(es): | [1] Missouri Univ Sci & Technol, Dept Phys, Rolla, MO 65409 - USA
[2] Jordan Univ Sci & Technol, Dept Phys, Irbid 22110 - Jordan
[3] King Fahd Univ Petr & Minerals, Dhahran 31261 - Saudi Arabia
[4] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Paulo - Brazil
[5] Indian Inst Technol Madras, Dept Phys, Madras 600036, Tamil Nadu - India
Número total de Afiliações: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | PHYSICA SCRIPTA; v. T165, OCT 2015. |
| Citações Web of Science: | 7 |
| Resumo | |
The N-color quantum Ashkin-Teller spin chain is a prototypical model for the study of strong-randomness phenomena at first-order and continuous quantum phase transitions. In this paper, we first review the existing strong-disorder renormalization group approaches to the random quantum Ashkin-Teller chain in the weak-coupling as well as the strong-coupling regimes. We then introduce a novel general variable transformation that unifies the treatment of the strong-coupling regime. This allows us to determine the phase diagram for all color numbers N, and the critical behavior for all N not equal 4. In the case of two colors, N = 2, a partially ordered product phase separates the paramagnetic and ferromagnetic phases in the strong-coupling regime. This phase is absent for all N > 2, i.e., there is a direct phase boundary between the paramagnetic and ferromagnetic phases. In agreement with the quantum version of the Aizenman-Wehr theorem, all phase transitions are continuous, even if their clean counterparts are of first order. We also discuss the various critical and multicritical points. They are all of infinite-randomness type, but depending on the coupling strength, they belong to different universality classes. (AU) | |
| Processo FAPESP: | 13/09850-7 - Disorder, Dynamics, Frustration and Topology in Quantum Condensed Matter |
| Beneficiário: | José Abel Hoyos Neto |
| Modalidade de apoio: | Auxílio à Pesquisa - Reunião - Exterior |